United States patents and articles of scientific literature cited in this application are incorporated herein in their entirety by reference.
The present invention relates to a method for the production of bovine growth hormone in yeast or E. coli by use of a synthetic gene. Bovine growth hormone is used to promote the growth of cattle, to increase the secretion of milk in cows and to elevate the efficiency of feed.
Synthetic steroids, for example, Estradiol (COMPUDOSE.TM.) by Eli Lilly U.S.A.; Estradiol benzoate (SYNOVAX.TM.) by Syntex, U.S.A. have been used in order to promote the growth of cattle and elevate the efficiency of feed provided to livestock.
But it has been found in developed nations including, the United States, that synthetic steroids remain in the body of livestock animals for a long time after they have been ingested when incorporated into feed and then have a detrimental influence when such products are consumed by humans. Thus, prohibition of their usage has increased.
On the other hand, because bovine growth hormone does not remain inside the body of an animal after being ingested and it demonstrates species-specificity, as it is a naturally occurring bovine protein, it is a more desirable feed additive than steroids. However, until the early 1980's it has not been readily available to the livestock industry since it is extracted from bovine pituitary glands and the amount has been limited.
The present inventors have discovered that bovine growth hormone may be produced economically and in large quantity in yeast or E. coli by using gene manipulation and so accomplished the present invention.